1. Technical Field
The present invention pertains to a Refrigeration Capillary Tube Inside Suction Line Assembly (RCTISLA), which provides improved heat transfer between the cool gaseous refrigerant, conveyed by the suction line, and the warm liquid refrigerant, conveyed by the capillary tube, during the well known refrigeration cycle in a conventional refrigeration system.
2. Description of the Related Art Including Information Disclosed Under 37 CFR 1.97 and 1.98
It is known in the art that placing a capillary tube inside a suction tube or line assembly will result in higher heat transfer as a result of the increased surface area with which the two media, namely the gaseous and liquid refrigerants respectively, are in contact. The present invention permits the noted heat transfer, from the warm liquid refrigerant to the cool gaseous refrigerant, to occur across the complete capillary tube circumference through only the one, single, tubular, wall of a cylindrical capillary tube.
The prior art has addressed both the structure of a RCTISLA and the method of manufacturing such assemblies in the manner set forth in the patent literature, as exemplified by the following: U.S. Pat. No. 2,133,961 to Buchanan; U.S. Pat. No. 2,530,648 to Cahenzli, Jr. et al.; U.S. Pat. No. 2,847,835 to Cooper et al.; U.S. Pat. No. 4,147,037 to Gelbard et al.; U.S. Pat. No. 6,305,188 B1 to Park; and EPO Patent Application No. 0 426 061 A1 to De Nardi.
U.S. Pat. No. 2,133,961 to Buchanan, in FIG. 2 discloses a refrigerant heat exchanger which includes a liquid refrigerant conduit that is located internally of an evaporator conduit. While the liquid refrigerant conduit enters and exits the evaporator conduit, no details are provided as to the structured of the entry and exit portions, how the refrigerant conduit is retained, or how the assembly is manufactured.
U.S. Pat. No. 2,530,648 to Cahenzli, Jr. et al., in FIGS. 1 and 2 discloses a heat exchange device which includes a liquid refrigerant tube entering one end of a casing and exiting at the opposite end. While the refrigerant tube is located within a casing, there is no mention of the mechanism for contacting, locating and fixedly retaining the former relative to the latter.
U.S. Pat. No. 2,847,037 to Cooper et al., discloses a capillary tube inserted in a punched out aperture of a connector tube. It is noted that after insertion thereof, the capillary tube is brazed or welded in place at its point of entry, while the inserted portion thereof rests against the inner peripheral surface of the connector tube. It is specifically set forth that the aperture, required for insertion, be pierced or punched, rather than drilled, in order to provide added material support, such as in the manner of a flange, for the capillary tube. Securing but one end of the inserted capillary tube can lead to vibration and subsequent rattling and can cause problems during subsequent further deformation of the completed assembly that may be required for specific installations. In addition, piercing and punching a tube can easily result in undesired deformation and variable quality.
U.S. Pat. No. 4,147,037 to Gelbard, et al., in FIGS. 2, 5 and 6 discloses, as best seen in FIG. 2, a refrigeration heat exchanger which has a capillary tube passing into and out of the suction tube at connections at 36 and 38, that may be made by soldering or brazing. No details are provided in regard to the specific structures employed at connections 36 and 38, which appear to merely locate and contact the capillary tube, which is physically held in place by longitudinal ridges that are deformed to surround the capillary tube, in the manner shown in FIG. 6 and would appear to detract, by reason of their wall thicknesses, from the heat transfer between the capillary tube and the suction tube.
U.S. Pat. No. 6,305,188 B1 to Park, in FIG. 3 discloses a refrigerant heat exchange device that includes a capillary tube inserted into a connection pipe via opposed T-shaped first and second coupling elements that cooperate to guide the capillary tube in and out of the connection pipe. However, the first coupling elements need to be threaded on to both the connection pipe, as well as separate inlet and outlet pipes, and the second coupling elements additionally require a separate pacing element to leakage of the refrigerant.
EP Patent Application No. 0 426 061 A1 to De Nardi discloses a method of forming a refrigerant heat exchanger tube wherein this heat exchanger tube includes a capillary tube that is inserted thereinto. The heat exchanger tube includes a bent portion where a hole is drilled to enter the capillary tube whose leading end is thereafter passed through the heat exchanger tube and exits at a front end thereof. The capillary entrance hole, after the insertion of the capillary tube, is subsequently welded closed. Thus, the capillary tube has to be inserted through a hole and guided through the heat exchanger tube until it exits from the front end thereof. It is unclear how the tip end of the capillary tube is retained, relative to the heat exchanger tube. The manufacturing method pertains to a completely automated procedure not pertinent to the present invention.
None of the noted prior art structures pertain to the structure of the RCTISLA and the methods of its manufacture, as set forth in the present invention, which features placing a capillary tube inside a suction tube that has opposed, shaped, inner end portions that conjoin with shaped recesses in mating, adjacent female braze connectors, to initially physically contact, locate, and then fixedly secure in a fluid-tight manner, via subsequent brazing the capillary tube relative to the suction tube.